The present invention relates generally to an animal exercising apparatus, and more particularly to an animal exercising apparatus of an improved design which provides a means for variably displacing an exercising animal's weight such that stress upon its lower limbs can be reduced.
There have been many attempts to provide a suitable exercising device for animals of a general type having a treadmill apparatus upon which an animal either runs or walks. Examples of such devices are shown in U.S. Pat. Nos. 3,709,197; 3,952,704; and 4,095,561. Solutions to the problems of limb support and belt friction inherent in these devices were presented in U.S. patent application Ser. No. 052,348, now U.S. Pat. No. 4,227,487 which is incorporated herein by reference.
However, an injured or weak animal may not be able to place its full weight upon its lower limbs during exercise. Effective conditioning and rehabilitation of such animals, therefore, demands a controlled, progressive increase in required exercise effort. A number of devices have attempted to provide a solution to this problem by immersing the animal in a body of water so as to displace some or all of the animal's weight from its lower limbs. U.S. Pat. Nos. 3,424,133 and 3,691,995 are examples of such devices whereby an animal is exercised in a stationary water tank or swimming pool.
U.S. Pat. No. 3,691,995 teaches the use of a circular, concrete water-filled tank whereby an attendant supervises the animal while it swims around the tank. Such a tank, however, is limited in its utility since due to its permanent, recessed design, it cannot be transported to the location of the injured or weak animal. Additionally, construction and installation costs of a large, concrete swimming pool can often be prohibitive due to the permanent nature and size of the tank.
Another problem typical to large, installed tanks when utilized with injured animals is the relative inability to closely monitor and regulate the exercise of the animal. In U.S. Pat. No. 3,691,995, for example, the attendant stands on an island in the center of the tank and must physically pull the animal to safety on higher ground if necessary. Additionally, since these installed tanks are primarily designed to facilitate swimming rather than walking, they fail to incorporate any effective means for variably regulating displacement of the animals weight so as to progressively stimulate hock, ankle and limb exercise through a walking or running motion.
U.S. Pat. No. 3,424,133 shows the use of an exercising attachment utilized in conjunction with a fixed water tank. Though this invention discusses the variable displacement of animal weight by varying the tank water level and/or application of flotation devices to the animal, it fails to solve the aforementioned problems inherent with fixed tanks; namely, portability, cost and monitorability. Further, inasmuch as the need for an animal exercising device may be only temporary or transient, the stationary nature of a fixed, exercising tank inhibits the sale and transfer of such a device when one's need for its use has abated.
Finally, U.S. Pat. No. 3,598,088 teaches the use of a livestock dip apparatus to submerge an animal in a liquid solution contained within either a portable or permanently fixed tank. Such a device, however, presents a very costly and complicated structure necessitating physical raising and lowering of the animal. Additionally, a treadmill assembly, if incorporated therein, would necessarily have to accommodate total submersion within the liquid.
Consequently, there is a need for an animal exercising apparatus utilizing a treadmill assembly to confine the required exercise area as distinguished from a large tank or swimming pool; an efficient, low cost method of variably displacing a desired amount of animal weight; a structure allowing close observation and monitoring of the semi-submerged animal; and a portable exercising device which can be readily moved to a desired location and has potential resale value to the owner once the need for its use has abated.